1. Technical Field
The present disclosure relates to LED (light emitting diode) lamps and, more particularly, to an LED lamp having enhanced waterproofing.
2. Description of Related Art
LEDs are well known solid state light sources, in which current in a forward direction at a junction, comprising two different semiconductors, electrons and cavities generate light. LEDs provide advantages of resistance to shock and practically limitless lifetime under specific conditions. When deployed in a lamp, LEDs offer a cost-effective yet high quality alternative to incandescent and fluorescent fixtures.
An LED lamp generally requires a plurality of LEDs mostly driven at the same time, which results in a rapid rise in operating temperature of the LEDs. However, since the lamps lack effective heat dissipation capability, continuous operation of the LEDs can cause instability in light emitted from the LEDs. Consequently, the LED lamp usually comprises a heat sink contacting the LEDs to dissipate the heat generated thereby. When the LED lamp is used outdoors for illumination, dust and moisture may enter the LED lamp, causing current leakage or short circuit, or other contamination of the LEDs. A conventional waterproof structure of an LED lamp includes a waterproof gasket and a groove defined in an envelope which correspondingly covers the LEDs. The envelope is disposed on the heat sink. The waterproof gasket received in the groove is sandwiched between the envelope and the heat sink. However, this conventional structure requires multiple through holes defined in the envelope for multiple screws respectively extending through the envelope and screwing into the heat sink. For the envelope generally made from specific transparent materials, such as glass, the work in forming the through holes in the envelope is relatively difficult and may result in a high defect rate of products. In addition, rainwater can creep through the holes of the envelope to enter an inside of the LED lamp. Thus, such engagement of the envelope to the heat sink by extending screws through the envelope has drawbacks.
What is needed, therefore, is an improved LED lamp which can overcome the described disadvantages.